Author: Tim_Porter Format: MarkdownItexFixed a link and updated.
<a href="https://ncatlab.org/nlab/revision/diff/2-crossed+module/24">diff</a>, <a href="https://ncatlab.org/nlab/revision/2-crossed+module/24">v24</a>, <a href="https://ncatlab.org/nlab/show/2-crossed+module">current</a>